drivers/usb/gadget/function/u_ether.h

   1 /*
   2  * u_ether.h -- interface to USB gadget "ethernet link" utilities
   3  *
   4  * Copyright (C) 2003-2005,2008 David Brownell
   5  * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
   6  * Copyright (C) 2008 Nokia Corporation
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #ifndef __U_ETHER_H
  15 #define __U_ETHER_H
  16
  17 #include <linux/err.h>
  18 #include <linux/if_ether.h>
  19 #include <linux/usb/composite.h>
  20 #include <linux/usb/cdc.h>
  21 #include <linux/netdevice.h>
  22
  23 #define QMULT_DEFAULT 5
  24
  25 /*
  26  * dev_addr: initial value
  27  * changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx"
  28  * host_addr: this address is invisible to ifconfig
  29  */
  30 #define USB_ETHERNET_MODULE_PARAMETERS() \
  31         static unsigned qmult = QMULT_DEFAULT;                          \
  32         module_param(qmult, uint, S_IRUGO|S_IWUSR);                     \
  33         MODULE_PARM_DESC(qmult, "queue length multiplier at high/super speed");\
  34                                                                         \
  35         static char *dev_addr;                                          \
  36         module_param(dev_addr, charp, S_IRUGO);                         \
  37         MODULE_PARM_DESC(dev_addr, "Device Ethernet Address");          \
  38                                                                         \
  39         static char *host_addr;                                         \
  40         module_param(host_addr, charp, S_IRUGO);                        \
  41         MODULE_PARM_DESC(host_addr, "Host Ethernet Address")
  42
  43 struct eth_dev;
  44
  45 /*
  46  * This represents the USB side of an "ethernet" link, managed by a USB
  47  * function which provides control and (maybe) framing.  Two functions
  48  * in different configurations could share the same ethernet link/netdev,
  49  * using different host interaction models.
  50  *
  51  * There is a current limitation that only one instance of this link may
  52  * be present in any given configuration.  When that's a problem, network
  53  * layer facilities can be used to package multiple logical links on this
  54  * single "physical" one.
  55  */
  56 struct gether {
  57         struct usb_function             func;
  58
  59         /* updated by gether_{connect,disconnect} */
  60         struct eth_dev                  *ioport;
  61
  62         /* endpoints handle full and/or high speeds */
  63         struct usb_ep                   *in_ep;
  64         struct usb_ep                   *out_ep;
  65
  66         bool                            is_zlp_ok;
  67
  68         u16                             cdc_filter;
  69
  70         /* hooks for added framing, as needed for RNDIS and EEM. */
  71         u32                             header_len;
  72         /* NCM requires fixed size bundles */
  73         bool                            is_fixed;
  74         u32                             fixed_out_len;
  75         u32                             fixed_in_len;
  76         bool                            supports_multi_frame;
  77         struct sk_buff                  *(*wrap)(struct gether *port,
  78                                                 struct sk_buff *skb);
  79         int                             (*unwrap)(struct gether *port,
  80                                                 struct sk_buff *skb,
  81                                                 struct sk_buff_head *list);
  82
  83         /* called on network open/close */
  84         void                            (*open)(struct gether *);
  85         void                            (*close)(struct gether *);
  86 };
  87
  88 #define DEFAULT_FILTER  (USB_CDC_PACKET_TYPE_BROADCAST \
  89                         |USB_CDC_PACKET_TYPE_ALL_MULTICAST \
  90                         |USB_CDC_PACKET_TYPE_PROMISCUOUS \
  91                         |USB_CDC_PACKET_TYPE_DIRECTED)
  92
  93 /* variant of gether_setup that allows customizing network device name */
  94 struct eth_dev *gether_setup_name(struct usb_gadget *g,
  95                 const char *dev_addr, const char *host_addr,
  96                 u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname);
  97
  98 /* netdev setup/teardown as directed by the gadget driver */
  99 /* gether_setup - initialize one ethernet-over-usb link
 100  * @g: gadget to associated with these links
 101  * @ethaddr: NULL, or a buffer in which the ethernet address of the
 102  *      host side of the link is recorded
 103  * Context: may sleep
 104  *
 105  * This sets up the single network link that may be exported by a
 106  * gadget driver using this framework.  The link layer addresses are
 107  * set up using module parameters.
 108  *
 109  * Returns a eth_dev pointer on success, or an ERR_PTR on failure
 110  */
 111 static inline struct eth_dev *gether_setup(struct usb_gadget *g,
 112                 const char *dev_addr, const char *host_addr,
 113                 u8 ethaddr[ETH_ALEN], unsigned qmult)
 114 {
 115         return gether_setup_name(g, dev_addr, host_addr, ethaddr, qmult, "usb");
 116 }
 117
 118 /*
 119  * variant of gether_setup_default that allows customizing
 120  * network device name
 121  */
 122 struct net_device *gether_setup_name_default(const char *netname);
 123
 124 /*
 125  * gether_register_netdev - register the net device
 126  * @net: net device to register
 127  *
 128  * Registers the net device associated with this ethernet-over-usb link
 129  *
 130  */
 131 int gether_register_netdev(struct net_device *net);
 132
 133 /* gether_setup_default - initialize one ethernet-over-usb link
 134  * Context: may sleep
 135  *
 136  * This sets up the single network link that may be exported by a
 137  * gadget driver using this framework.  The link layer addresses
 138  * are set to random values.
 139  *
 140  * Returns negative errno, or zero on success
 141  */
 142 static inline struct net_device *gether_setup_default(void)
 143 {
 144         return gether_setup_name_default("usb");
 145 }
 146
 147 /**
 148  * gether_set_gadget - initialize one ethernet-over-usb link with a gadget
 149  * @net: device representing this link
 150  * @g: the gadget to initialize with
 151  *
 152  * This associates one ethernet-over-usb link with a gadget.
 153  */
 154 void gether_set_gadget(struct net_device *net, struct usb_gadget *g);
 155
 156 /**
 157  * gether_set_dev_addr - initialize an ethernet-over-usb link with eth address
 158  * @net: device representing this link
 159  * @dev_addr: eth address of this device
 160  *
 161  * This sets the device-side Ethernet address of this ethernet-over-usb link
 162  * if dev_addr is correct.
 163  * Returns negative errno if the new address is incorrect.
 164  */
 165 int gether_set_dev_addr(struct net_device *net, const char *dev_addr);
 166
 167 /**
 168  * gether_get_dev_addr - get an ethernet-over-usb link eth address
 169  * @net: device representing this link
 170  * @dev_addr: place to store device's eth address
 171  * @len: length of the @dev_addr buffer
 172  *
 173  * This gets the device-side Ethernet address of this ethernet-over-usb link.
 174  * Returns zero on success, else negative errno.
 175  */
 176 int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len);
 177
 178 /**
 179  * gether_set_host_addr - initialize an ethernet-over-usb link with host address
 180  * @net: device representing this link
 181  * @host_addr: eth address of the host
 182  *
 183  * This sets the host-side Ethernet address of this ethernet-over-usb link
 184  * if host_addr is correct.
 185  * Returns negative errno if the new address is incorrect.
 186  */
 187 int gether_set_host_addr(struct net_device *net, const char *host_addr);
 188
 189 /**
 190  * gether_get_host_addr - get an ethernet-over-usb link host address
 191  * @net: device representing this link
 192  * @host_addr: place to store eth address of the host
 193  * @len: length of the @host_addr buffer
 194  *
 195  * This gets the host-side Ethernet address of this ethernet-over-usb link.
 196  * Returns zero on success, else negative errno.
 197  */
 198 int gether_get_host_addr(struct net_device *net, char *host_addr, int len);
 199
 200 /**
 201  * gether_get_host_addr_cdc - get an ethernet-over-usb link host address
 202  * @net: device representing this link
 203  * @host_addr: place to store eth address of the host
 204  * @len: length of the @host_addr buffer
 205  *
 206  * This gets the CDC formatted host-side Ethernet address of this
 207  * ethernet-over-usb link.
 208  * Returns zero on success, else negative errno.
 209  */
 210 int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len);
 211
 212 /**
 213  * gether_get_host_addr_u8 - get an ethernet-over-usb link host address
 214  * @net: device representing this link
 215  * @host_mac: place to store the eth address of the host
 216  *
 217  * This gets the binary formatted host-side Ethernet address of this
 218  * ethernet-over-usb link.
 219  */
 220 void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN]);
 221
 222 /**
 223  * gether_set_qmult - initialize an ethernet-over-usb link with a multiplier
 224  * @net: device representing this link
 225  * @qmult: queue multiplier
 226  *
 227  * This sets the queue length multiplier of this ethernet-over-usb link.
 228  * For higher speeds use longer queues.
 229  */
 230 void gether_set_qmult(struct net_device *net, unsigned qmult);
 231
 232 /**
 233  * gether_get_qmult - get an ethernet-over-usb link multiplier
 234  * @net: device representing this link
 235  *
 236  * This gets the queue length multiplier of this ethernet-over-usb link.
 237  */
 238 unsigned gether_get_qmult(struct net_device *net);
 239
 240 /**
 241  * gether_get_ifname - get an ethernet-over-usb link interface name
 242  * @net: device representing this link
 243  * @name: place to store the interface name
 244  * @len: length of the @name buffer
 245  *
 246  * This gets the interface name of this ethernet-over-usb link.
 247  * Returns zero on success, else negative errno.
 248  */
 249 int gether_get_ifname(struct net_device *net, char *name, int len);
 250
 251 void gether_cleanup(struct eth_dev *dev);
 252
 253 /* connect/disconnect is handled by individual functions */
 254 struct net_device *gether_connect(struct gether *);
 255 void gether_disconnect(struct gether *);
 256
 257 /* Some controllers can't support CDC Ethernet (ECM) ... */
 258 static inline bool can_support_ecm(struct usb_gadget *gadget)
 259 {
 260         if (!gadget_is_altset_supported(gadget))
 261                 return false;
 262
 263         /* Everything else is *presumably* fine ... but this is a bit
 264          * chancy, so be **CERTAIN** there are no hardware issues with
 265          * your controller.  Add it above if it can't handle CDC.
 266          */
 267         return true;
 268 }
 269
 270 #endif /* __U_ETHER_H */